Research On The Critical Lubrication Condition Parameters Of Hydrostatic Bearing Oil Film

Hydrostatic bearing is a vital processing device in the equipment manufacturing industry.Meanwhile it is also a representative product in the whole industry of our country.As the core component of CNC equipment,its performance will affect the working efficiency of the equipment.During the operation of the hydrostatic bearing,the oil film thinning and lubrication will be destroyed due to the change of working conditions and internal fluid friction and heating.Especially when the oil film is in the local zero flow state of critical lubrication,the temperature rise will be aggravated,which will affect the machining accuracy and operation reliability of the machine.In this paper,the Q1-205 double rectangular cavity hydrostatic bearing is taken as the research object.The analysis of lubricating oil flow characteristics and temperature rise characteristics under different working conditions in critical lubrication condition is carried out in the light of the characteristics of lubricating oil flow and temperature rise.According to method of combining theoretical Analysis,Simulation and Experimental Verification.The main research contents are as follows: firstly,based on hydrodynamics,tribology and lubrication theory,the mathematical model of bearing oil film is established,and 3D model is carried out by UG.The lubricating oil film model of a single oil pad is meshed with ICEM-CFD software,and its quality is improved by means of O type mesh and mesh encryption.Secondly,the finite volume method is used to simulate the critical lubrication state under the condition of known load and known rotational speed respectively,In order to obtain the fluid flow state at the oil side of the countercurrent side seal,what is taken as the criterion of the critical lubrication state of the oil film.Simultaneously the temperature field distribution of the whole lubricant film can be obtained,moreover it reveals the characteristics of the oil film temperature rise under different working conditions.Finally,the temperature field of oil film under different operating conditions is tested by designing experiments,in addition verify the theoretical analysis and simulation.It is found that the high temperature region at the countercurrent side of the oil film sealing edge of the hydrostatic bearing has a tendency of diffusion to both sides of the sealing edge,and it becomes more obvious with the increase of load and rotational speed.When the oil film is in critical lubrication and local zero flow state,the cross section flow of oil side seal through countercurrent is almost zero.The heat accumulation phenomenon is serious,because the heat can not be taken away in time lead to the local temperature rise is increased.